Truck Gives A Brief Stall When Accelerating From Idle

paani99 · June 6, 2008

Hey everyone,

I just got my truck (1986 GMC K-15 w/305), it kind of stalls when I push on the gas from a stop. It idles fine. Then if I push on the gas lightly it stumbles a little and then gets going. If I push on the gas heavily from a stop it doesn't really stumble, just if I push lightly from a stop. Sorry, seems like I am repeating myself. Any help you can give me would be great. Treat me like a rookie because that's what I am. Thanks in advance for the help.

2000DV4.8 · June 6, 2008

I'd change the fuel filter first.

98silvz71 · June 6, 2008

Hey everyone,

I just got my truck (1986 GMC K-15 w/305), it kind of stalls when I push on the gas from a stop. It idles fine. Then if I push on the gas lightly it stumbles a little and then gets going. If I push on the gas heavily from a stop it doesn't really stumble, just if I push lightly from a stop. Sorry, seems like I am repeating myself. Any help you can give me would be great. Treat me like a rookie because that's what I am. Thanks in advance for the help.

I would freshen the whole engine up. New plugs, wires, check distributor, fuel filter, oil and filter, etc.

Squirrely · June 6, 2008

Hey everyone,

I just got my truck (1986 GMC K-15 w/305), it kind of stalls when I push on the gas from a stop. It idles fine. Then if I push on the gas lightly it stumbles a little and then gets going. If I push on the gas heavily from a stop it doesn't really stumble, just if I push lightly from a stop. Sorry, seems like I am repeating myself. Any help you can give me would be great. Treat me like a rookie because that's what I am. Thanks in advance for the help.

I would freshen the whole engine up. New plugs, wires, check distributor, fuel filter, oil and filter, etc.

I just fixed a similar problem. (check the Ask Tech forum) My egr was bad, then I was sold the wrong one. Took a few days to figure this out.

Like the other guys said; plugs, cap, wires, roter, fuel filter are all good to replace. If that doesn't work, try the EGR.

For fun just pull the vacuum line from the egr to see if the stumble goes away. I'm gonna bet it does. Also plug the vacuum line so your carb doesn't gulp down air when you do this.

Genuinefine409 · June 7, 2008

Hey everyone,

I just got my truck (1986 GMC K-15 w/305), it kind of stalls when I push on the gas from a stop. It idles fine. Then if I push on the gas lightly it stumbles a little and then gets going. If I push on the gas heavily from a stop it doesn't really stumble, just if I push lightly from a stop. Sorry, seems like I am repeating myself. Any help you can give me would be great. Treat me like a rookie because that's what I am. Thanks in advance for the help.

Do you know if the accelerator pump is ok? when they start wearing out they get a little play between the pushrod and the diaphragm and when you gently push the throttle it doesn't move the pump right away because of the play and the engine will stumble due to lack of fuel. Might not be whats wrong but doesn't hurt to check it out.

Magnumb · June 13, 2008

I have the same issue on my 1995 Yukon. Where is this Accelerator Pump located. I was looking on Rock Auto for it but had no luck.

Thanks,

Justin

95Sierra2500 · June 13, 2008

I have the same issue on my 1995 Yukon. Where is this Accelerator Pump located. I was looking on Rock Auto for it but had no luck.

Thanks,

Justin

You don't have one on your '95. An '86 has a carburetor, your '95 should be fuel injected through the throttle body unless it's been altered. I'll almost guarantee yours is an EGR problem, but a tune-up wouldn't hurt.